Carburetor



F. E.. Asi-:LUNE

June 5,v 1928.

CARBURETOR Filed April :m 1922 neetsfsnee't 2 QOOO 000 Mm. y www i i imetenteel inne 5, lle/St retirez Prieur oFFIcE.

E. ASELTINE, 0F DLYTN, OEM), SSGE'OR T0 GENERAL MGRS RESEARCH GR- PGl'lION, 0F DAYTON, GEIQ, A CORPRTIOH @E DELAWARE.

nomination sied pril 1:1, rese.

This invention relates to earburetors, especially those designed t'or supplying an atomized fuel mixture to an internal combustion engine.`

' Among the objects of this invention is to provide a Vacuum or self-lifting \,rouretor which will supplyv a properly proportioned fuel mixture to the engine throughout the great variations in loads and speeds to which the engine may he subjected. A great detect in all previous seit-lifting carburetors has been that eithei` the vacuurn which it has been necessary to maintain in order to littthe fuel varies .so greatly that the correct proportioning of the niirture supplied is interfered with.` or that under some conditions o1" engine operation the lifting vacuum tells to a point Where it is unable to litt sullicient fuel for the engine. y'l'his invention is designed to overcome these difficulties.

Among the more specitic objects ot the invention is to provide for an adjustment of the richness of t ie mixture at small loads entireli7 independentlyv of the richness at full loads: to provide a compensating by-pass around the main fuel atoniizing venturi in order to give a more uniform mixture under various oeratino conditions; to )rovide a valve in the main air inlet which automaticallyv produces a constant or slightlv decreasing vacuum in the inlet as the iiow ot air therethrough increases to provide a manual control 'for varying the richness of the mixture by relieving the vacuum in the iuel chamber; and to provide a novel accelerating Well tor supplying an extra rich mixture upon sudden opening ot the throttle valve.

AFurther objects and advantages of the present invention will be apparent from the following description` reference being had to the accompanying drawings, wherein preferred forms ot embodiments oi' the present invention are clearly shown.

ln the drawings:

Fig. 1 is a plan view ot the CarbiiretOiand shows various duct-s and passages in dotted lines; I l I Fig. 2 is a section on'line 2-2 ot Fig. l land shows the top part of the main atomizing venturi and coml'ensating toy-pass for Serial No. 554,2i9.

rendering the mixture therefrom more un1 torni; u

` Fig. 3 is av section on lineB-S of Fi 5, and shows the means for drawing fue? up into the accelerating Well; Y

Fig. 4 is a section on line ll-f'i o Fig. 5 and shows the manually controlled air valve 'for relieving the vacuum in the float chamber;

Fig. 5 is a section on the 'irregular line 5-5 ot Fig. l which is so taken to show a section throu h theacceleiating Well and its suction pro ucing means and tuel exit nozzle;

Fig. 6 is a section on line 6-6 of Fig. 1, and shows the booster venturi tor maintaining a vacuum in the float chamber;

Fig. 7 is a section on line 7-7 of Figs. l and 5 and shows the fuel exit, nozzle of the accelerating well; l

Fig. 8 is a. section on line 8 -8 of Fig. 6 and-shows the ball hearing means for the automatic main air valve;

Fig. 9 is a section on line 9-9.of Fig. 1 and shoivs the means for adjusting the richness ot the mixture at small throttle openings bv using the relatively high vacuum above the throttle Valve to increase the vacuuru in 'the float chamber to a greater or less extent. i

Fig. l() shows e. modified form of the automatic main air valve.

Similar reference characters refer to simii lar parts throughout the several Views of the drawings.

In Fig. 5 numeral 20 designates the com stent. level fuel chamber Which is supplied with fuel through the inlet 2l, the constant level being niaintained'by the valve 22 which is operated by the float 23 in the well known manner. The main fuel atomizing means comprises the venturi 25 which draws fuel from the float bowlf20 up through the passage 26 into the annular space 27 and from thence into the venturi through the metering holes 28 et the throat. The venturi 25 is sup- 1 plied with au' through the primary air inlet 30 extending up through the center oi'- t-he float. bowl 20. The rich mixture produced by the venturi 25, passes up- Ventmi mixe el, which is n ms: ouml-.ig o. o mi 'running lies im E passage Ml@ 'zhe ivi-eli mxime 'is ieael 'miao lae annuler spose @il which ne lieiween lie wells oi 'the maxim eeezio@ il? me? the secondary sepemely iormed omi elipped'flowo in the mein doei of elle l eerbu'etor. The moin me supply for the engine enlews hzeogli lne air hom 'i2 niiet pastime loe automatic @mimo openeed. valve 50.; Tie Section el elle engine aetiognfroio lie eerlmieaor i3 llews eine mom am @pene 9A; einem foei *level bowl by me following meme.

...um op :or zmeely comme@ momma one moli oi hoezo i2 log. meme of elle peeolier fome oi' 'e-.uomoie emotion, ooneed visive l?. The eeceobiie pi'vos ori the wie@ aliviaee eine naive eo tha@ its lowei" aree .525 is eoieiiieeeisiy ,lese than @he upper mee liiie is nia) pxoviiiefl. with im ezcuoe l l i ened Jportion 511, es cleanly shown m Fig. 59 which pz'e'veiiis ille valve )Timm ies upper @ile mnfcil fai-'Lio velve lios remixed cloted posiiioo. 59. il; ie geen time wheel e di'e'enoe of pfeesm'e ikea loom eeeotefi on ille two' sides of ehe valve, like to;

swing inwaeily since ii@ ood oil' will be allowed i looiom of the valve onooleo the iop. lie volw i reeifeinefl by ille couille? *.@Jeiglia 55 wlniei'i brings it beek 2o clos/eel poeitioo es ehe suo-1 sion in oir hom i2 @lies down. The 55 ie so olispoeed met the center of oseilleion einourb pivot 5l" o the .veigliij of entime volw is locotedeppioimetely position le is lime eeen that es elle wlw swings; to loe Willey: positions ei festive @il weiglie io ense lle vaive deeeosee andi .eee. elle 'orrgue necessary o hold. the volw, open grows less elle valve opens Wide. due to the lip 5e. the e3- eetive afee. of the upper pari of lie valve Ii'emein eoosian fof: awhile nml then fle-- creas-es slowly es tile valve opens while tine o'ecoive eren, of the lower mit decreases much mom rapidly; hence he amount of.

42 lo bolli valve 50 in its Wider "positiono is less than the amount to hold it only elig'hly open. Il. 'nid @Heet 5G open more which mods to hold valve opening increases io y#che of 4ine valve will area is @Meier eme? ist :at lle Wider poeiiooe easily es its magie of widen Preferably im of ehe Weighi 55 Whig. eei'e Le e mme sto hold lie valve open when le et Wide angles. one, two, or all three of einem ofeee be use@ o cause ille suciioe. im. ei? nom 4.2 to remain approximately Cons-tam or preferably to decrease slzghftly ee elle amouni; of oir owing to the enigme iceees, filme is, as the valve opens o. flash poi 57 is px'ovied ico' pie-vene 'valve 50 from @uttering egiceseively., which flash poi may be @Lilley en or oil damped emi of my well known construeim suelo es that illufsti'ated in Fig. 5, or any oihei' desieefl fono. l0 shows e modi leaioo wherein the weiglli .5&5 is eubs-ited by ehe light tension 'e ring; .58 :suitably .moooefl el: euch an eng ethno iis. eeeiive @lese valve 50 decreases es eine volvo *ze 'wide positions, which will be ob- .rom T O. For the @impose of "ving gi'eeei effect mille Spring; 58 W' en ci, iie hele@ 529 me piovifleol ie eet e 4e emiog; :it suela on angle ee .ifo give it o eoei leverage upon ille valve e@ wide po ooo The vom 118 seives as e meeiae'o op the doeii poe piston ood ois'he .ome mme eels similarly ifo ibo lower en@ oli ilse weight es deocriiled einfwe. io assisiiogg eo iiolf the velv'e open when in Wide oeiioos by lie impingement of the enermg thereupon. Thus it is :geen as @he aliment of eik? flowing to lie engine in emes-ee, ie es the lfirotle l5 is opened wiaie, elle veeuum @ai 'oir hom 42 decreeses Rims peirmiting greeer volumetric eeiency :wel :im'iqfuemly greater power from the engine. The vacuum in spese 24 in the float bowl is maintained by; e 'ooostex"s venturi 6() (see 6) leading from the atmosphere imo eine oir hom 4:2 through ille passage 6l ond o. smalley passage 62 leading from space 24 into the throat of the venuri through the smell holes 63 as clearly illustrated in Fig. 6. The booster vent-uri is preferaloly designed to give about twice as much depression in space 24 mayfexist in the air imm 42 ai any time. Since the depression in space 42 Will not vary greedy from l mercury 'the depression in space 24; Wili not vary .ieatly from 2 mercury which will be sufficient lo lili fuel from lie fuel tank (not shown) up ino the lozicbowl Q0 through flue?. 2l. l

sieben? above lie automatic eil' valve 5G is so edjusecl thai when the engine is under full load the vacuum in air horn 42 gradually deefeases as the engine Speed increases, hat is, ille yvaffuum in 42 preferably decreases 'from approximaely 1.1 mercury et 400 R. to approximately .9" mercury at 2.00() R. 1P. M. This decrease would neoesserilyenieil o proportional decrease in remise since the boostei Gil is a constant. multiplier, that is, the vacuum in the space 2a diie to the booster 60 would decrease from 72.2 at 4C() R. P. M. to L8 at 2G90 E. l?.

Such a change in the vacuum above the fuel surface in the lloat bowl would greatly interfere with the richness .of the fuel mixture produced by the mainV yenturi 25, and especially so since the vacuum in passage 100 increases from approximatelyll mercury at 400 engine R. l. M. to approximately 32 mercury 'at 2000 R. P. M. ln orderfto overcome an excessive increase in richness of the mixture from venturi due to the combined ,effect ot these two causes, a compensating by-pass is'piovided between the exitend of vent-uri 25 and the space Q4 above the liquid fuel (see Fig. 2). The bly-pasa 7G is preferably formed in an easily removable plug 73 SorenY threaded into passage Tel to permit easy changing of the size' of the oypass for adjusting the carburetor for differs ent engines or conditions. Passage T4 is led into the interior ot rotary valve through the small hole 71 and the port 72 in valve 35 which remains in constant register ivith hole 7l. Now it- 'will be seen that when the vacuum in passage 100 is approximately 1.1 mercury at a0() R. P. M. the vacuum in.

speeds the'fdownward air flow .through by' pass 70 gradually reduces to zero somewhere between 1000l and 1500 R. P. M., then changes direction to an upward flow and gradually increases lwith the engine speed.

fllie degree of Vacuum obtained in space 24 is in part regulated by the size of the bypass duct 70. The duct 7G may be a simple inetering plug, however, it desired, an upwardly opening' check valve 75 may be located in plug 73 which has av duct 76 therethrough which Therefore when the airflowv is upward the check valve 75 is lifted from its seat and the effective size oi the lay-pass is that of duct 70; but when the airllow is downward valve 75 is closed lleavinfr only the smaller duct 76 as the effective size ot the by-pass. The effect of checir \'alve 75 is to increase the vacuum in space 24e at. the higher engine speeds above the usual 2 maintained at the lower speeds, in order to prevent the mixture becoming too rich at the higher speeds.

vin the float bowl.

is smaller than 'the passage 70.'

A manual means .for adjusting the richness of the mixture from venturi 25 is also provided. A breather duct 80 leads through the Wall of casting 19 trom the space 24 to the port 81 (see `Figs. Il. .5 and l). A groove S5 of gradually tapering depth (see Fig. 4) is cut in the cylindrical wall of the rotatable valve 35 to register with the port 8l and the port 82 of the duct 83 leading to the atmosphere. As the valve 35 is rotated manually by means o the rod 3R connected to the arm 39 integral with valve 35, the tapered groove restricts more or less the passage oi atmospheric air through duct 83 into duct S0 and thence to space 24. By this means the vacuum in space 24 may be adjusted manually troni the dash by the operator when at any time. he desires a richer or leaner mixture. lt will be noted that vvalve 35 may be rotated through an angle suliicient to give the proper travel to the breather valve 85 Without interfering vvith the registering oi ports 36 and 37 by making port 36 of sutlicient Width (ses Fig. l).

For starting purposes, the valve 55 is `rotated clockwise as viewed in Fig. 1 until port in the upper part of valve 35 registers with port 91 which leads through the passage 200 in casting 19 to the outlet i3 of thc carburetor through the annular space 93 and the holes 92 above the throttle valve. 45. When valve 35 has been thusrotated. port 36 ivill have gone out of register with the passage l0() which is thereby closed oil', and the tapering breather `valve 85 Will be in a positieii to allow "ree llow of atmospheric air through ducts 83 and S0 to the space 24 lt `is thus seen that in starting. there is :i very 'slight or no vacuum on the fuel -in the float bowl and the high suction onthe venturi 25 due to its being connected to passage 200 which is in turn connected to the engine intake above the throttle 45, resul' in a rich mixture. ThisV use of valve 35 for starting is somewhat similar to and is used at such times as thc air choke valve inordinaiy carburetors. As soon as the engineis Working properly the lever 39 is shifted back to its ordinary running position as shown in Fig.y

1. The valve 35 is retained against axial niotion by the scievv which has a point 87 projecting into a circumferential slot 8S cutv in the 'all of ialve 35 (see Fig. 5). Preferably the ends. ot' the slot 88 are so deter-- mined as to act with screw 8G as stops for Athe limiting positions ot the valve 35.

lVhen the engine. is runningr under light loads` that is Ywhen it has higher speeds for only a small opening of throttle 45, a different set of vconditions exist throughout almost the ent-ire carburetor. For instance, at an engine speed oie-400 R. P. M. and light load the vacuum in air horn 42 will be only llt) ebene .7 er meifemy efaeezzpeeq the il melee heeey eeds, me meme; to' the pimary me thzieegh venan 25 hem@ more needy able m seis'fv the engine 'suespace would inter'ele )with the mixme properemms as Wei es pesslby be msuhcgene Tte. reieeehe neirom iee mem fue tank te jfs for i'eguetng ehe vacuum' in spsee 21E; dwing 'maaier heavy leeds.

eermeerzn.seeing bypass by thismeens mest f @beamed by an inde xendeni; zeguleien m? the vacuum m spece Se it Eghe leeds since mixue feg? Eig-he eedzs em-y he vused @Le engine with mit e'ecine; 'deze kin eff mxime which Wi he obtained amec heavy eads. v`"lfmefme here has eeen pmvec the passage zeroufgh casting i9 K( Figs. l and 9) Beadng 'from space Q4 hmugh ehe edju'stab'e valve 102k om time passage l20G through the hole 103. und thence the tu'ottle valve 45. New when the vacuum in space 24 tends to fall to 1.4 or 1.03" 'at ligh'oeds as above described, the very high vacuum above @le fhxee 45 aceimg through passage 200. hne Gi-3, .reslictng vave i633 mld due; 161 wi cause sir 'fo nw up through this peseegfewsjf and ztms inceese gxe 'vacuum le. space The wve 10.95 is ndjmstee by nppying e screw driver "zo screw T104; md by hs means :my desired vacuum n 2li ard 'zeneeany dcsiz'ed richness et' mixture may be ohnied at ight loads. Preferably e vacuum of 2.1 or 2.2" is nmmained in space 24 by adjusting e screw 104. s Hw em en he engine increases the hree 5 is opened Wcer and simutnneousy he heh vacuum smve ze Hmu'e decreases zm. et fm2?. epee. 'ehz'ee me "vacuum 'i'mh abm'e and bee'w 'he Hneie 45 ifa e Same und enh/f slighy above {fha-ai'. in Hee air here 42. As seen es the vacuum ae the haies 92 fails beew about 2 mercury *fixe ew womh passage 101. would 'everse :m air would enfer space 24. To prevent this :i check vave 105 is provide-d which prevens such leverse of @uw and eemeqnen'v pem'niisduei' lOl to function onv :et such Mmes when th'otte 45 is closed ever 2 nercurv :Pneve hefhrntte. Uf eeuwse if esred, cheek valve 105 may se smm tensione?. m' Weigghte olmd ii ce until the vacuum abo-ve hmtte 45 o the space aboli/e passing to the eng-ne fpaefes *through the idling ube connecting the ower annular space 4:0 "io the upper szmum' space 93 and ent hrough hees B2. H ehe mimure is es cessivey rich et this (Reed ding pesion. m ''amee e5, e dues T36 may be a'ovded. leed ing imm the smel pork 10'? immediee'y' above :the bep e he ihmttle valve i5 ewn ms the pesssge im.. Since he passage HB5 thee theugh the waive 102 it is deviene @met .se hm eme peslen of the nofe 45 the pweege permls s Eugee vacuum to be Hee?. bowl 20 shan at any ciber ime. As seen as 'thme 45 'opened the sighesa ammini ehe met 1.07 is shut DE' or falls beew @he ehree emi hence gees out ce? en, `eevimg "he cfmdut 2Q@ mugl hoes 92 and ehe sdjusng waive 02' i@ Piske care of he Egh' ined eejustment. Uf cem'se duct N6 may be emced Withou aiecting ehe poper functioning; ef other parte of .the cmvbmeeern :and in many eases .it is ne@ necessans or esimble.

neombination wfah this carburetor here has eso been llusmed en accelerating well 'whose function is 0 cause he carburetor to suppy a temporary extra .rich mixture whenever the thretle valve is suddenly Opened., thus presenting ae eng-ne melng en such Occasions anf a' ii.' s melf-e eaeppy acceleration. The meting-g is prevfec with the wei space H5 5 3) ecated @have che fue@ eae in he @am bew 20. mei ms e duct Eea-ding "ema 521i@ he fuel herein and pmvle 'vs''a e chec,V veve 11'? permiing; fue! to flew @ely in ehe irecion from the @est bowl io ehe Wel 115. The we Ue aso has a duet H8 eading upward and ie eomeeef ee "ehe vacuum passage Q00 thieugh the ss'm ees 20 in e ping 19 (see 3). This plug E19 :s also pevided with s wey 3.5211 edngj wie the emosphere which sii, 1 37 li L? lan was eadngg ifo he high veezmm passage 280. These hees 1520 n ways 1521 md 122 are so promr''ienec reai'vejf.' ie each other hat he high vacuum, ranging 'from l0 to 20"' mex'- cmy, e'dns'y obtainable at par?. uole in passage 200 will be maintained n vacuum in the :xcceerang Well H5 of something like 21V/4 2 mercury. which being gi'eatez than the vacuum in space 24 wil liquid fuel. through check valve M7 sm duet H6 and the We space V15. A Vexv slight emeunjf" of fue' wi he drawn thzougx the hoes 1%? :md passage 200 and en Le fhe engine bu he Sme si? eM the hoer' in plug* 1.3.9 maybe mede se smei es 'ke maske vhie mty-? neutres appreciahle. The lower part of Well 115 isA maintain a vecuuin in the well space 115 ot about :2l/2 mercury as above descrihetl. Hence fuel Will he drawn up through noch 117 and lill the entire Well space, the .choc-ir valve 126 closing:l in the ineantinie to pre-- vent the vacuum in the well being relieved by air from the air horn 4t2. Nov-v when the throttle is suddenly opened the vacuum in passage 200 immediately falls to something like 1 mercury. Since the way 121 in plug 119 is considerably larger than Wtiy 122, atmospheric or will new pass from way 121 flown through holes 1:20 and relieve the suction in the Well space 115. The check valve 117 ot course Will now close und the Vacuum of approximately 1in theair horn 452. will open. the check valve 126 anti spray the uel out into the entering air through the relatively large nozzle 12T. As soon as the throttle is again closed sufficiently to build up a high Vacuum in passage 200 the action of plug 119 reverses and again builds up u vacuum in the Well 115 above that in the iioat howl, hence Well 115 again fills up with fuel and remains so until the throttle is opened to a Wide position.

is thought that the structure weil as the operation of this invention will he perectiy clear to those skilled in the art troni the shove description taken 'with the drewings. lt may he Well however to point out more -particula-rly certain 'details oit construction which are of special importance or sdvan'tsge. lt is important that the oooster venturi 6G he Well packed to prevent leakage rozn the atmosphere around it into the cluct 52. F or this purpose u gasket 6l has heen used in this particular case t is also important that the venturi 25 he Well packed at both ends in order thet any leakage around it into space may not interfere with the richness oi' the mixture produced by it. F or this purpose gaskets 31 and 32 are used and the 'venturi' is pressed in tight contact with the gaskets by nie-ans of the screw plug 33. The venturi 25 is easily removable hy retrieving the rotary valve 35 enti applying a screw driver to the slot Sel in plug 33. Por rliiierent engines or flixercnt conditions ot operating, citlerently designed venturies 25 may-loe used to give 'the correct mixture Without varying the other parte: of the cai-huren.

Since the automatic air vulve should oyerate with as little friction as possible so that will inuintsin the seine pressures during the opening nioven'xent es during the closing` movement, its spindle 51 may loe ro yvided with ball hearing support-s es i. us-

trstetl in 8L hulls ll) are supported by the screw threaded plugs 131 which are screw threaded into smell bosses onthe air horn e2 and provided with loclr nuts 132 as clearly illustratedn While the forms et' mechanisms herein 1. ln e fuel lifting carburetor for verim able speed engines, a constant level fuel chamber, e passage communicating therewith above the normal level of fuel therein, ineans acting` through said passage to pro luce a vacuum in seid chamber tending to decrease slowly as the euginespeeds up; a Venturi tuoe constituting a primary fuel utomizing means and receiving fuel from the constant level chamber, the vacuum at the suction enti ot' said venturi increasing as the engine speeds up; and s compensating duct between the suction end of ,the venturi and the space shove-the fuel in the constant level chamber, whereby the richness of the atomized mixture is rendered more uniform as the engine speed varies.

2. ln a titel lifting carburetor7 a fuel reservoir, ineens communica-ting therewith operstive 'to produce therein a vacuum tending to tlecrease as the engine speeds a Veuturi tube constituting a fuel atomizing means und; receiving fuel from the fuel reservoir, the vacuum at the suction end of the venturi increasing es the engine speeds up; a ily-passl duct between the suction end of the venturi and the spese shove the liquid in the fuel chsmloerto cause the venturi to give a more uniforuimirture as the engine speed varies.

' '8. `ln a carburetor having a main induction passage angl a throttle valve therein: e high vacuum chamber in. communication with the space alcove `the throttle vulve and" arranged to cleliver fuel mixture thereto; e' fuel reservoir ellectively closed to the atmosphere and having means tovrneintain a relatively constant vacuum therein compared to the widely varying engine suction stiflitional means connecteti to the high vacuum chamber tor increasing the vacuum in the Yfuel reservoir when the throttle is in nearly closetl positions; and means to rendersaid adtiitional ineens inoperative When the throttlc is open to Wide positions.

Ll. ln a carburetor having e mein incluetion passage and a throttle valve therein: a high vacuum chamber in connnunication with the space above the throttle valve. und errangeol to deliver uel mixture thereto; s.

- chembee. foi' imox'eeeieg vacuum in pinete emi hsv/'ieg tiveiy eoesem meme?, i1

iiie Wicieiy wegging esi, ed tioleei m *les comceiei io fue high seem io she aimes e sei-7.

foei reservoir when sise iis-ome is is meeiiy closed osifzioosg and e eiieeii veve 'eo ciose seni s dmoneimeens ii'om faire iuei sesso tiene.

5. En s. eerbureior having e izhifoeeie emi e, fuel bow?. wherein e suiieimespiisric pisseuse is meimained, in combinaties; e. fiiei chembei, s, foei uci ieeciiug 'iom @diie foei bovvi to eeici cheminer, e one wey iiovv mesma im seid duct, means for (ii-ovvio@ i'uei into sei-:i chamber by fthe vacuum eitiove the thsoiie when seid throteie izoweils iis closed giositiom, smi ineens isi: disohei'giii-Le; imei said chamber imo the Mesi', passing hiougb the cerbureigoi when @he ehi'oiiie is epenee.,

6. In e earbmeto having :i mixiotiie emi, a fusi bowl wherein, e. substmospheic pres sure is meimtein'eei, in combimeiciom e foei cheminer, s. foei. duct kamin@ from @he fue?. bowl ivo seid chemises', meses for direi/ving fuel into seid chemises 'by faim veouwii .shove the iiiotiie when ssii?. lbiiszocie is o'wsis iis closed posiitice, e iiiei ssii. fiom seid cham bei iisving s, me 'may mesme iheieilo soci dischergixog into eine biais?, through ihe ceriom'eioi', and mesme for incvessimg Ehe voressui'e im seid cheminer shove that et the foei exit when the ihotie :is opened, whereby Jiiei is'ciisciierge imo che bissi.

7. csrbmezor ies veriebie speed eogines compi'iszog e uei 'eservoir, im stemming moons supplied with uei from seid reservoiz by suction, the suciioii eiiieczieg soppiy of fuel izo seifi means emiing' eo immessey es the engine speed increases, meses for producing vacuum in seid reservoir, and supplementary Vvacuum producing memes, means for increasing the vacuum in seid reservoii` se the engine speeds up.

8. A carburetor comprising e foei rcser voir, e fuel etomizing ineens .including s veniuri to which 'foei is supplied from 'seid reservoir, ihe sucion eective to suppiy uei 'to the ssi ventui'i tending to increase as engine speed increases, e primary 'means operativeto produce a vacuum in seid resesvoir and e, secomiery ineens also operative to produce ze. vacuum in seid reservoir he total vacuum tending ,to imeieese es the en gine speed increases.

9. Stiucture as set forih in claim 8,.the said secondary means comprising e passage leading to the reservoir from ehe mixure passage beyond the seid venturi. 10. in eine] iiftiug ceiburetor'ior veriebie speed. engines, a, foei ffeservoir, meses for producing berein s, vacuum tending ifo be shove the@ desired foi' low engine speecis om comps-,ssii wi;

bei@ v time @esimo 'oi? high engine vee w imo seid ssesivoii eeiis om! withdrawing sie:

eegiee epeeiis. f f- .zei iieing cmiiuz'etoi, o.' tizi'oiiie viee, e. giesssge ieiivering mimmo from seid;

vacuum ihm is produced in said reservoir,

means iov conveying i'uei rom said roseovoiito seid see-spiedo unifier the inuence of seid higher vacuum, meses im discharging ehe *ii-'oei seifi reeepieeie into the sin' suyo-ij; passage, and means im pevenizing iioiv siiiough seid. :iiscieorge meses imo seid i'ecepieeie sind femm @ow ihi'ougle! seid connecting means into said reservoir.

i3. im engine cerbureior having e fuel i'eseivoii and primary and auxiliary airsupply pesseges, anni means for drawing fue! into seid reservoir by snoeien comprising e. pioreiiiy of vecuom produeiiig; devises indepemieeiiy eoimeciefi to ssic'i ieseivoir, the eiecipive sucios. in ssiei, i'eservoii lbeing the resultase of joins sind simultaneous acioo of seid devices, one of said. devices being aected. by conditions of sii' o'vv'in the rismi meses rendered eiiecive we i mary passage and zmoiiei' by the conditions of ow in me euxiiiesy passage.

14. A carburetor heviiug a fuel reservoir, si prima@v mixing veiiiuii and a second mixing devies adapted io suppiy auxiiiaiy air o the rich minime suppiied thereto from ihe seid venuri, means for drawing fusi. imo the veservoir by suction comprising a plurality of vacuum pioducing devices independeniiy connecied io seid reservoir, the e'ective sucion im seid rervoir being the i-esuiient; of tine joint and simultaneous action ofi `seid vacuum producing devices, one of said devices being aected bv icheow oi' the auxiliary eii-4 and mother ing affeced by che vacuum on the delivery side of the seid primary venturi.

reservoir, ein intake passage and a fuel nozzle iherem from which iuei is caused to fiow by suction, e piiimiity oi independenivmeans for prodigioingve vacuum in be fuei rosen# voor, iviieieby she eeotive suction 'm sani its fr. Vv

engines comprising a constant reservoir is the resultant of the ioinl; enti simultaneous action of all of seid inelee pendent .rucuuni producing means, said vacuum producing ineens comprising a plu-- rality or conduits connecting the intelte passoire :mi i'uel reservoir, each ot sind conduits ewinz/itely noting us u suction psssuge und :i uieuns ornelmitting nu: tossici fuel reser:`

'.l. A cneiurctor for internal combustion engines comprising e construit le inet' reservoir, un intake passage having e throttle, a lfuel nozzle therein from which fuel is caused to flow by suction, means for producing u' vacuum in said fuel reservoir which and a supplementnry'meens independent of seid tlrst mentioned means for producing; e vacuum in said fuel reservoir which ,decreases 'the throttle is opened, whereby the vacuum in the fuel reservoir is main tained nearly constant throughout Wide Variations in engine speed.

17. A cnrhuretor lor internal combustion engines comprising a constant level fuel.

reservoir, un intake passage having' n throttle, a fuel nozzle therein from 'which fuel is caused 'to flow by suction, n suction passage for producing n vacuum in said fuel reservoir which increases as the throttle is opened and a 45secondi. suction passage tor producing a vacuum in said fuel reservoir which decreases es the throttle is opened,

'both ot" said suction passages communicating with the intake passage anterior to the throttle vulve.

18. i carburetor for internal combustion level fuel reservoir, su intake passage having e..

' throttle, :i fuel nozzle therein from which engines' eo ervolr. un intuire pusezzige lowing a throttle, n fuel nef/,nie them-:u from which Jiuel is cuusetl lo low hy f on, means for produc ing :i vacuum in seul fuel reservoir which increases as the throttle is opened. and a plus i'ulity of supplement:try ineens for produc` ingw u -vacuum in suiil fuel reservoir which decreases as the throttle opened.

20. A curhurem' for iufrnul-coinloustion engines comm-lenig u constant level fuel reservoir. un intake passage haring u throttle, u luel nozzle therein from which t'uel is increases as the throttle is opened 'u vulve for -ing 'fuel to the intake caused to tion' by suction, means for producing a vacuum in seid fuel reservoir which increases es the throttle is opened, unil u pluruiity of supplementary ineens for pondu@ ine a vacuum in said. tue-l` reservoir which ile 'es us the throttle is opened, one of seid supplementary ineens comprising o suc tion passage connecting the fuel reservoil with the .intake passage posterior y to the throttle vulve. l

2 A carburetor ior internal combustion engines comprising constent level uel res ervoir, on intuire passage a throttle, s fuel nozzle therein troni which luel is conseil 'to 'low by suction, u primar-y ineens for producing u vacuum in seiC4 fuel reservoir which increases as the throttle opened comprising u suction passage connecting the fuel reservoir with the intuire passage, und s plurality of supplementary menus tor pro ducing a vacuum in said fuel reservoir which decreases as, the throttle is opened, one of seid means .comprising n suction poss-ige connecting the fuel reservoir with the intel-:e passage on the same side of the throttle seid primary vacuum producin nieens.

22. A carburetor for interna 'combustion engines, having in combination, a constant level fuel reservoir, a primary mixture pas sugehaving t'uel and air inlets, a primary mixture conduit conveying mixture to the,

engine for normal operation, u supplexnenn tory conduit for conveyingprimary Amixture to the engine for starting purposes, means 'for producing# u partial ,Vacuum in the fuel reservoir unoer ull operating conditions, inc-ins t'or udmitting oir to the fuel chamber to reduce the partiel vacuum therein, and simultaneously controlling both said mixture conduits and said air admit4 ting menne..

22%. i curburetor for linternal combustion engines.- l'iaving in combination, n constant level fuel reservoir, an nir intake passage, a primary conduit for conveyingr fuel to the intake passage l'or normal operation of the engine, a. supplementary conduit i'or conveypurposes, ineens for maintaining a subutniospheric pressure in thejuel reservoir :it all times when the engine, is running, means for admitting nir to the fuel reservoir to reduce the Vacuum therein, und means for simultaneously rendering etectiv said sup pleinentury tucl conduit and air admitting ineens.

2e. lln a 'fuel lifting carburetor, the combination ot' un nir intuire passage, e. moin fuel reservoir. nieuns oiwnroducin u veel.

lun therein under ull conditions of engine operation to li'lt 'fuel thereto *from the main i'uelsupply, u fmpplciueuturj.' liucl reservoir connected to suiil luuin 'fuel reservoir. u dischnru'e passage connecting suiil reservoir with the intake passage, nieuus for producpussage Ifor sturting- 

